Flexible electrical conductor



(No Model.)

' H. B. LYTLB.

FLEXIBLE ELBGTRIGALGONDUGTOR.

Patented Sept. 4, 1883.

N. PEYERS. mmwgmphu. vlamingen. u. C.

'l UNITED 'STATES PMENTA OFFICE.

HENRY s nYrLn, `or BosToN; MAssAcHUsnTrs.

` FLEXIBLE ELECTRICAL CONDUCTOR.

`SIEECIFEIIGATION' `forming part of Letters Patent No. 284,216, ,dated September 4, 1883.

Application tiled May 7, 1883. e (No model.)

To all whom, it may concern/f Be it known `that I, HENRY B. LYTLE, of

i Boston, in the county of Suffolk and State of phonic and telegraphic switch-boards, and for i use in connection with many other forms of electricalapparatus.` Heretofore such conductors have been made of insulated straight wire,`

which is too readily broken, of fine wire coiled spirally and covered with insulating-tubing of tinsel,or of a steel spiral inclosing one or more copper or brass conductors. The latter forms,

i @though more durable than the former, are still very fragile, and, moreover, are comparatively costly and expensivein manufacture, and diffitirely separate conductors, and can thus be cult to` connect with the metallic tips, which are in every case requisite to form the connection of the cord with the binding-screws to which it is to `be attached.

The object of. my present invention is to provide an elastic and flexible insulated conductor and durable means of connecting the same to a metallic plug, and to provide a double conductor in each flexible cord, of a character adapted for practical use in connection with the manipulation of metallic circuits.

My said inventionconsists, first, in substituting a ribbon of spring-steel, of hard copper, or other suitable metalor alloy, for the conductors heretofore used; in combining the same with a flexible and non-conducting protecting-l` ternal protective covering two of the said ribbon-steel con ductors', separating them by a nonconducting substance, which also divides the terminal plugs, so that each flexible conducting-cord from tip to tip consists of two enused conveniently in the manipulation of lo ops or metallic circuits.

y In the accompanying drawings, Figure l represents a flexible conductor constructed in accordance withmy invention, and showing the external form. Fig. 2 shows the method of connecting the conducting part to a tip when l great flexibility is not desirable at thetipconnection. Fig. 3 shows the planof connecting the tip,whereby a sudden strain at the point of connection is prevented. `Fig. 4 is a crosssection of the complete conductor on the line w a: of Fig. 1. Fig. 5 is a representation of the 6o conducting-ribbon tipped, but unprotected by the insulating-covering; and Fig. 6 shows the l uncovered conductors arranged in duplicate for use inmetallic circuits. As shown in Fig. 5, the actual conducting part simply consists of a narrow and thin ribbon, of spring-steel or `other elastic metal of any suitable length. I have obtained good results from a ribbon fof steel three-sixteenths of an inch wide and onehundredth of an inch thick. In the drawings the metal band a is show as being tipped with a switchboard plug, B,

lat oneend, while the other end is provided `with a screw-tip, C, adapted for attachment lto any permanent binding-screw terminal. It is obvious that any other form of tip may be `equally well fitted to the steel ribbon, but `since I have used l.these forms I have for convenience adopted them in this specification.

possessing great strength; to provide simple j view` ofrthe end C, the tip has an incision,

c', sawed into one end, and terminating in" a round hole a little larger than the width of the incision. The said incision is made just wide` enough to admit the end of the steel ribbon a, 8 5 and a drop of solder is then applied to the junction, which is thus made homogeneous.

Fig. 3 shows in actualsize the ribbon end as tted with a switch-plug, B. This consists of a metal shank, b, ofthe size and shape corresponding to the hole inI which it is to fit, attached to the metallic ribbon a in the manner described. The upper part, f, of the shank` b surrounds the slit or incision in which the steel ribbon is fixed, and is externally threaded f or the reception of a tubular thimble or guardpiece, c. This guard-piece is internally threaded atits lowerfend, but at its upper end expands into a flaring oriice, e. The utility of this is evident.' l

Although the band or ribbon c is in all ordinary cases extremely ilexible, it is in telephoneswitching operations subject to sudden and `abrupt bends, which taking place at the point IOO b', would be very apt to break the steel ribbon short off. By the use of the hollow guard piece or protector c, which screws onto the shank, this is prevented, and the depth and filare of' the orifice e produces a gradual bend in all such cases.

Before attaching the tags or end pieces the insulating and protecting covering is placed round the conducting-ribbon. I prefer to use 1o a simple tube of vulcanized rubber, A, which may ,be slipped over the conducting-ribbon a,

and which is kept in Yplace by the flanges g of the several tips. This fits loosely, as shown in the cross-section, Fig. 4, in which a repre- 'sents the conducting-ribbon and A the inclosing-tube.

If desired, awoven covering may be adopted instead of the rubber tube, but for most purposes the tube is the best, because it is much 2o cheap er and more easily supplied and replaced.

Fig. l shows the cord as it appears when completed, A being the external coating or non-conducting covering; B, the switch-plug or tag at one end thereof, consisting of shank 2 5 b and guard-piece c, and C being another form of tip or terminal applied to the other end. A flange, g, at both ends is provided,which serves to hold the flexible covering in place.

n In Fig. 6 I show a cord provided with a 3o double conductor and adapted for use in conend of the cord, irrespective ofthe length thereof.y The tips or metal terminals of such a cord are also completely divided by the insulating medium, which is made to correspond in shape to the conformation of the tip terminal or plug, as shown in section in the drawings, in which, at one end, the plug B is shown, having its two sides, b and b2, electrically divided by the non-conductor i, yet forming mechanically a homogeneous whole. The tubu- 4 5 lar guard-piece c is made in one metallic piece,

as in other forms. The plug B and opposite terminal, C, may be both separately manufactured, with a hard-rubber partition between 4the two semicircular metallic plates, and in for a single conductor.

Having now described my invention, I

.claiml. A flexible electrical conducting-cord composed of an elastic metallic ribbon, metal terminals or tips therefor, wherebythe said ribbon may be connected with electrical circuits or apparatus, and a non-conducting covering for the said metallic ribbon, consisting of a vulcanized rubber tube loosely surrounding the same, substantially as hereinbefore described.

2. The hereinbefore-described stem or tip for flexible electric cords, consisting of a conf ducting-shank, slitted for the connection of a flat flexible conductor, and provided with a tubular guard-piece at its inner end, substantially as and for the purpose described.

3. The combination, in a flexible electrical conducting-cord, of a steel-ribbon conductor, a metal plug forming a terminal therefor,V and. a tubular guard-piece screwed or otherwise attached to the inner end of the said plug, and

.providedwith a flaring orifice, whereby the steel conductor is protected from injury, due to sudden bending at the point of attachment tothe plug, substantially as specified.

4. The hereinbefore e described method of forming the connection between a ribbon-like metal flexible lconductor and a metallic tip therefor, which consists in cutting an incision or slit in the end of the said tip, in inserting theend of the ribbon in the said slit, in making the joint homogeneous by soldering, and, finally, by encircling the junction by a tubular guard-piece which laps, by means of a flaring extension, over a portion of the ribbonlike conductor, for the purposes described.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, this 4th day of May, 1883.

HENRY B. LYTLE.

Witnesses: p

J. H. CHEEvER, GEo. WILLIS PIERCE. 

